Nonaqueous electrolyte secondary batteries, typified by lithium-ion secondary batteries which have a high energy density and are of high capacity, are widely used as power supplies for driving the present-day portable electronic devices such as mobile phones, mobile personal computers, and mobile music players and as power supplies for hybrid electric vehicles (HEVs and PHEVs) and electric vehicles (EVs).
These nonaqueous electrolyte secondary batteries, in general, have a positive electrode plate and a negative electrode plate. The positive electrode plate is composed of a positive electrode core, such as an elongated sheet of aluminum foil, and a positive electrode mixture layer formed on both sides of the core, the mixture layer containing a positive electrode active material which stores and releases lithium ions. The negative electrode plate is composed of a negative electrode core, such as an elongated sheet of copper foil, and a negative electrode mixture layer formed on both sides of the core, the mixture layer containing a negative electrode active material which stores and releases lithium ions. These nonaqueous electrolyte secondary batteries are manufactured by, as also disclosed in PTL 1 below for example, winding a positive electrode plate and a negative electrode plate into a cylindrical shape or an ellipsoidal shape with the two plates isolated from each other by a separator to form a wound electrode body, optionally compressing the wound electrode body form a flat wound electrode body if the battery is a prismatic one, connecting a positive electrode tab and a negative electrode tab to a predetermined portion of the positive electrode plate and the negative electrode plate, respectively, and then covering the outside with a sheathing body.